avanzini sealevelchanges.whatissaidaboutit

7/27/2019 Avanzini Sealevelchanges.whatissaidaboutit

1/17

ROUNDTABLEROUNDTABLE


2/17

SEALEVELCHANGESSEALEVELCHANGES WHATISSAIDABOUTIT?WHATISSAIDABOUTIT?

Carlo AvanziniCarlo Avanzini

ProfessionalEngineer,MWWDChairmanProfessionalEngineer,MWWDChairman


3/17

, ,, ,

ahotsubject.ahotsubject.

Thepress

is

emphasizing

the

catastrophic

potential

effects

The

press

is

emphasizing

the

catastrophic

potential

effects

(ordenyingthemassciencefiction),contributingtotheperplexity(ordenyingthemassciencefiction),contributingtotheperplexity

ofthepeoplewhichstartstoaskforactionsofthepeoplewhichstartstoaskforactions butarepracticalbutarepractical

act ons

poss eact ons

poss e

,,

TableonthepotentialdangersofthechangeinthesealevelsTableonthepotentialdangersofthechangeinthesealevels

dueto

global

warming.due

to

global

warming.


4/17

Question:Question:

Willweface acatastrophicriseinthesealevels,Willweface acatastrophicriseinthesealevels,

endangeringcoastal

towns

and

marine

structures,endangering

coastal

towns

and

marine

structures,

ortheseawillbehave?ortheseawillbehave?

cultivategraininLapland?cultivategraininLapland? andthearcticicemeltingandthearcticicemelting waterwillwaterwillcoveralllowlandscoveralllowlands arecommon aswellthoseontheCO2emissions.arecommon aswellthoseontheCO2emissions.

Thesound

of

many

different

bells

finds

resonance

The

sound

of

many

different

bells

finds

resonance

in allmomentsofourlifethroughthemedia.in allmomentsofourlifethroughthemedia.


5/17

Justincase,wearetryingtoprovidetosomebandJustincase,wearetryingtoprovidetosomebandaidsaids

safe uardin Veniceandstartin tomake lansforHollandsafe uardin Veniceandstartin tomake lansforHolland butbut

whatabout

lowlands

around

the

world,

which

already

suffer

what

about

lowlands

around

the

world,

which

already

suffer

fromlandfromlandoriginatedfloods?originatedfloods?


6/17

n e ewa er nas n ora a u , ewa er eve n ar sn e ewa er nas n ora a u , ewa er eve n ar s

oceansisnotthesameeverywhere;sealevelvarieswithlocationoceansisnotthesameeverywhere;sealevelvarieswithlocation

tides,winds,andwaves,includingstormsurges.Sealevelrisestides,winds,andwaves,includingstormsurges.Sealevelrises

whenoceanswarm,anditdropswhentheycool(becausewaterwhenoceanswarm,anditdropswhentheycool(becausewater

expandswhen

it

heats

up

and

contracts

when

it

cools).

expands

when

it

heats

up

and

contracts

when

it

cools).

Regionalvariationsinsealevelcanpersistformanyyears,evenaRegionalvariationsinsealevelcanpersistformanyyears,evena

eca e. n er y nga esec anges s es owerr sean a neca e. n er y nga esec anges s es owerr sean a n

globalaveragesealevelasiceagesrecedeandadvanceoverglobalaveragesealevelasiceagesrecedeandadvanceover

(fromNASA,ScienceMissionDirectorate)(fromNASA,ScienceMissionDirectorate)


7/17

ThismapshowsglobalThismapshowsglobal

patternsofchangesinseapatternsofchangesinsea

level(sea

surface

height)

level

(sea

surface

height)

measuredbysatellitemeasuredbysatellitebasedbased

throughtheendof2007.throughtheendof2007.

Placeswhere

the

sea

Places

where

the

sea

sur ace eig tincrease upsur ace eig tincrease up

to225millimeters(aboutto225millimeters(about

8.9inches areshownin8.9inches areshownin

darkred;

places

where

sea

dark

red;

places

where

sea

leveldroppedareblue.leveldroppedareblue.

ThemostwidespreadchangeinsealeveloverthistimeperiodwasanThemostwidespreadchangeinsealeveloverthistimeperiodwasan

.

.

spannedbythisimage,aclimatepatterncalledthePacificDecadalspannedbythisimage,aclimatepatterncalledthePacificDecadal

Oscillationwasinitswarmphase,andseasurfacetemperatureswereOscillationwasinitswarmphase,andseasurfacetemperatureswere

aboveaverageinmuchofthebasin.Thermalexpansionduringthisaboveaverageinmuchofthebasin.Thermalexpansionduringthis

warmphase

would

be

consistent

with

arise

in

sea

level.warm

phase

would

be

consistent

with

arise

in

sea

level.


8/17

ChangesinthelocationorvelocityofoceancurrentsovertheChangesinthelocationorvelocityofoceancurrentsoverthe

span

of

decades

can

be

part

of

a

natural

cycle,

or

they

may

span

of

decades

can

be

part

of

a

natural

cycle,

or

they

may

resultofhumanresultofhumancausedclimatechange.causedclimatechange.

SatelliteobservationsofsealevelfromsatellitessuchasSatelliteobservationsofsealevelfromsatellitessuchasTo exTo ex

Jason1,

and

the

recently

launched

Jason

2,

are

critical

tools

for

Jason

1,

and

the

recently

launched

Jason

2,

are

critical

tools

for

scientiststryingtounderstandhowglobalwarmingwillaffectscientiststryingtounderstandhowglobalwarmingwillaffect

oceanheatstorageandglobalsealevelriseovermanydecades.oceanheatstorageandglobalsealevelriseovermanydecades.


9/17

InternetandpresscontributetotheanxietywithinformationInternetandpresscontributetotheanxietywithinformation

SealevelstorisedramaticallySealevelstorisedramatically

et s:et s:

Hig ti es,stormsurgesan waveactioncancausecoastaHig ti es,stormsurgesan waveactioncancausecoasta

flooding.SealevelsinpartsofScotlandwillhaverisenbyflooding.SealevelsinpartsofScotlandwillhaverisenby

about

30cmb

the

2080s.....about

30cm

b

the

2080s.....

ResearcherswereanalyzingtheriskofcoastalfloodingandwaysResearcherswereanalyzingtheriskofcoastalfloodingandways

tomanageit.Morethan300coastalfloodssince1849werestudied...tomanageit.Morethan300coastalfloodssince1849werestudied...

was oun a s orms r ven n rom e an c cean ur ngwas oun a s orms r ven n rom e an c cean ur ng

periodsofstrongwesterlywindswerethemaincauseofcoastalperiodsofstrongwesterlywindswerethemaincauseofcoastalflooding.Overthepastfewdecades,waterlevels50flooding.Overthepastfewdecades,waterlevels5060cmabovethe60cmabovethe

highestpredictedtidehavebeenrecordedatAberdeen,LerwickandhighestpredictedtidehavebeenrecordedatAberdeen,Lerwickand

Stornowayand120cmatMillport.Stornowayand120cmatMillport.

about20cmhigherintheClydeestuary,about20cmhigherintheClydeestuary,28cmhigher28cmhigherinMorayandinMorayand

AberdeenshireandAberdeenshireand32cmhigher32cmhigherintheNorthernIsles....intheNorthernIsles....


10/17

Large"eye"berg.PhotoOceanQuestCharterLarge"eye"berg.PhotoOceanQuestCharter

Arewefacingannewglacialeraoraperiodoficemelting?Arewefacingannewglacialeraoraperiodoficemelting?

Weare

rea ng

a

an

t e

contrary

o

a ...

an

t e

more

we

We

are

rea ng

a

an

t e

contrary

o

a ...

an

t e

more

we

read,themorewedonotunderstandwhatishappening.read,themorewedonotunderstandwhatishappening.

IntheAgeofSail,knowledgeoftheworld'soceancurrentswasaIntheAgeofSail,knowledgeoftheworld'soceancurrentswasa

must.A

collaborative

study

between

Spanish

and

German

must.

A

collaborative

study

between

Spanish

and

German

researchershasdiscoveredforthefirsttimehowsmallvariationsresearchershasdiscoveredforthefirsttimehowsmallvariations

insurfacewindssignificantlychangedtheoceancurrentsoftheinsurfacewindssignificantlychangedtheoceancurrentsofthe

previousort t ant c. esec angesmay ave eenrespons e ort eort t ant c. esec angesmay ave eenrespons e ort e

abruptclimatechangethatoccurredduringthelastglacialpabruptclimatechangethatoccurredduringthelastglacialperiod.

rs ScientistshavenowboththeclimaticsimulationsaswellastheScientistshavenowboththeclimaticsimulationsaswellasthe

reconstructionsat

their

disposal,

both

of

which

indicate

that

reconstructions

at

their

disposal,

both

of

which

indicate

that

variationsintheAtlanticOceancirculationcouldhavebeenthevariationsintheAtlanticOceancirculationcouldhavebeenthe

keymechanismresponsiblefortheabruptclimaticchangethatkeymechanismresponsiblefortheabruptclimaticchangethat

oo p aceover e ceage.oo p aceover e ceage.


11/17

An iceberg waterfall. Photo Ocean Quest ChartersAn iceberg waterfall. Photo Ocean Quest Charters

Thenyoureadthat:Thenyoureadthat:

IthappenshoweverthatsincesomemonthstheatmospherehasIthappenshoweverthatsincesomemonthstheatmospherehas

changed...notonlymeteorologically.Again,somescientistschanged...notonlymeteorologically.Again,somescientists

presentacontradictory

hypothesis

...

The

magazine

Nature,

for

present

acontradictory

hypothesis

...

The

magazine

Nature,

for

instance,hasrecentlyexplainedthatbetween 2010and2020instance,hasrecentlyexplainedthatbetween 2010and2020

wew acea ras cre uc ono eear empera ure ue owew acea ras cre uc ono eear empera ure ue o

thecoolingoftheAtlanticocean...andthepastmonthathecoolingoftheAtlanticocean...andthepastmontha

not...)thearcticicesaremelting,theanctarticicesincreasetheirnot...)thearcticicesaremelting,theanctarticicesincreasetheir

thickness ...andthisiswhathappensduringthecenturiesthickness ...andthisiswhathappensduringthecenturies


12/17

Whatfrom

the

practical

standpoint?What

from

the

practical

standpoint?

Willwefindourselves,oursonsandgrandsons,obligedtotakeaWillwefindourselves,oursonsandgrandsons,obligedtotakea

liftfromanynavigatingcreatureormakeshiftbarge?liftfromanynavigatingcreatureormakeshiftbarge?

ono n so.ono n so.

Evenifitmaybepossiblethatthescenariowillchange,theEvenifitmaybepossiblethatthescenariowillchange,the

generations.generations.


13/17

Whilescientists

seek

the

if

&

why,

we

engineers

may/will

have

While

scientists

seek

the

if

&

why,

we

engineers

may/will

have

tofacethepossibletechnicalproblemswhichageneralizedriseintofacethepossibletechnicalproblemswhichageneralizedrisein

waterlevelmay/willcause.waterlevelmay/willcause.

, ,, ,

byafractionofmeter,willupsetallthedischargehydraulics...byafractionofmeter,willupsetallthedischargehydraulics...

possibleflooding

of

the

coastal

WWTP,

to

the

influence

of

high

possible

flooding

of

the

coastal

WWTP,

to

the

influence

of

high

wateronbreakwaterandjetties...tothelossofwidecoastalwateronbreakwaterandjetties...tothelossofwidecoastal

areas...areas...

. .


14/17

NEXT:NEXT:

IanLarsenIanLarsen Canwerelyonmathematicalmodels? Physicalmodellingstudy

Murali

MuraliKantharajKantharaj

Impacts

of

Climate

Change

on

Indian

coasts

a

perspectivetofuture

ChristopherMeChristopherMead CoastalDefence Vulnerability2075assessmen o ec ange ncoas a e ence vu nera ycause y

globalclimate

change

over

the

next

75

years

Dov Rosen Assessment of climate chan e induced im act via sealevelrise,waveandwindclimateandanthropogenicactivityonthe

coastsof

the

Mediterranean

DiscussionDiscussion


15/17

Assessmentofclimatechangeinducedimpactviasealevelrise,Assessmentofclimatechangeinducedimpactviasealevelrise,

oftheMediterraneanoftheMediterranean

DovRosen,B.Galanti,A.Golan,L.RaskinDovRosen,B.Galanti,A.Golan,L.Raskin

SummarySummary :Theforecastedsealevelriseinducedbyglobal:Theforecastedsealevelriseinducedbyglobal

warming,as

well

as

the

forecasted

increase

in

the

frequency

of

warming,

as

well

as

the

forecasted

increase

in

the

frequency

of

extremestormconditionsinducedbyclimatechangeimpactonextremestormconditionsinducedbyclimatechangeimpacton

windandwaveclimatestatisticsposedangerstomanycoastalwindandwaveclimatestatisticsposedangerstomanycoastal

,,

ispresently

in

amild

erosive

state,

presenting

both

beach

erosion

is

presently

in

amild

erosive

state,

presenting

both

beach

erosion

andcoastalcliffsretreat.andcoastalcliffsretreat.

AcoastalengineeringhydroandAcoastalengineeringhydroandmorphomorphodynamicstudywasdynamicstudywas

performed

by

the

authors

in

order

to

provide

guidelines

for

a

performed

by

the

authors

in

order

to

provide

guidelines

for

a

nat ona po cy ocumentont emanagemento t ecoasta c snat ona po cy ocumentont emanagemento t ecoasta c s

inviewoftheirpotentialincreasedcollapseandsetinviewoftheirpotentialincreasedcollapseandset

, . , .


16/17

es u y nc u e assessmen o presen sea eve r se ora mees u y nc u e assessmen o presen sea eve r se ora me

horizonupto2100(+1.0m),increaseoftheprobabilityofmorehorizonupto2100(+1.0m),increaseoftheprobabilityofmore

watersignificantwaveheightforanaveragereturnperiodof100watersignificantwaveheightforanaveragereturnperiodof100

yearsforthesametimehorizon)andinvestigatedmitigationyearsforthesametimehorizon)andinvestigatedmitigation

means.Wave

setup

and

means.

Wave

setup

and

runuprunup impact

and

profile

erosion

were

impact

and

profile

erosion

were

investigatedoncoastalsectorscoveringover60kminlengthbyinvestigatedoncoastalsectorscoveringover60kminlengthby

CEDASsoftwarepackage,usingagridsizeof10mfromdeepwaterCEDASsoftwarepackage,usingagridsizeof10mfromdeepwater

to the cliff to SWAN and 5m SBEACH .to the cliff to SWAN and 5m SBEACH .


17/17

TheoutcomeindicatedthecoastalcliffsectorsmostsensitiveTheoutcomeindicatedthecoastalcliffsectorsmostsensitive

mitigativemitigative solutionisbyutilizationoflowsubmergencesolutionisbyutilizationoflowsubmergence

detachedcaisson

breakwaters

chains

remote

from

the

coast.

detached

caisson

breakwaters

chains

remote

from

the

coast.

TheseinduceapermanentrelativelylowTheseinduceapermanentrelativelylow

wavesetup(>1.5m)butdiminishalmostcompletelythewavewavesetup(>1.5m)butdiminishalmostcompletelythewave

a ac ng ec sun eranyseas a econ on, encea ac ng ec sun eranyseas a econ on, ence

enablingapermanent

protective

means,

consisting

of

the

enabling

apermanent

protective

means,

consisting

of

the

submer ed caisson chain lower art of the cliff toe rotectionsubmer ed caisson chain lower art of the cliff toe rotection

bypermanentmeanslikegeotextilesacsorbypermanentmeanslikegeotextilesacsorgeotubesgeotubes combinedcombined

withasingular

artificial

sand

nourishment

of

the

cliff

toe

and

with

asingular

artificial

sand

nourishment

of

the

cliff

toe

and

beach.beach.

avanzini sealevelchanges.whatissaidaboutit

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